/****************************************************************************
** 
** MIT License
** 
** Copyright (c) 2021 shaoguangcn
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#ifndef SPINLOCK_H
#define SPINLOCK_H

/**
 * \class spinlock
 * \brief Realization of spin lock with C++ atomic variables
 *
 * You can use std::lock_guard like:
 * \code
 *      std::lock_guard<spinlock<>> lock;
 * \endcode
 *
 * \note Do not sleep during the lock period.
 */
template<typename T = void>
class spinlock
{
public:
    spinlock() = default;
    spinlock(const spinlock&) = delete;
    spinlock& operator=(const spinlock&) = delete;

    inline void lock()
    {
        while(flag.test_and_set(std::memory_order_acquire)) {
        }
    }
    inline void unlock()
    {
        flag.clear(std::memory_order_release);
    }
private:
    std::atomic_flag flag = ATOMIC_FLAG_INIT;
};

#endif // SPINLOCK_H